MANILA, 27 September 2013 (IRIN) - Experts in the Philippines are warning of further possible landslides in the north of the country, less than one week after the southwest monsoon rains brought on by Typhoon Usagi displaced more than 100,000 people and left 30 dead.

“We’re on the lookout for rain-induced landslides and are currently conducting [a] pre-emptive evacuation in the areas that were most affected when the rains hit,” Graciela Macabare, provincial disaster risk reduction and management officer for Zambales Province, told IRIN. Zambales has experienced nine landslides.

Local DRRMC numbers estimate some 275 families from three towns in the province have already been relocated to four evacuation centres.

Nearly 600,000 people across six provinces [Bataan, Zambales, Rizal, Batangas, Cavite, Occidental Mindoro] have been affected by the heavy rain which began on 23 September, and more than 123,000 remain displaced, the Disaster Risk Reduction and Management Council (DRRMC) said on 27 September. The displaced are being sheltered - 86,186 are staying with family and friends, while 20,753 are in 103 evacuation centres.

New threat

Now, just days later, another tropical depression, “Paolo”, is on its way, with winds estimated at 55kph and its centre just 290km west of Zambales. The province is about 230km north of Manila, the Philippine capital, and is among those already badly hit by Typhoon Usagi.

“The mountain sides are still heavily saturated with water. Even rain that is not strong, but is continuous, may cause further landslides,” warned Ricardo Otero, DRMMC municipal officer and administrator of Zambales.

However, many residents are not heeding the warning and are staying in their homes. “The public areas that were supposed to be used as evacuation centres were also flooded during the heavy rains. We did not know where to go,” said 41-year-old Jerwin Rivera. “Now, cleanup operations are ongoing and these places are still muddy.”

Rivera said that they had never seen the water rise so high or so quickly. “We had sandbagging efforts to prepare for the coming of the monsoon. It [the barricade] was up to 4 feet [1.22 metres] high, but the waters still exceeded it. How can you prepare for that?”

Better preparedness needed

“The weather trend is that areas that were never flooded are now experiencing flooding. It is always ‘unprecedented’, so people are not used to it,” said Gwendolyn Pang, secretary general of the Philippine Red Cross. “We have seen this happen already many times and, as a result, the poor become poorer. Before you can recover from one typhoon, there is another one coming.” She called for better information, such as geo-hazard maps, to improve planning and adaptive capacities at the local level.

The archipelago nation experiences an average of 20 typhoons a year between the months of June and December. The government has developed geo-hazard maps highlighting areas prone to natural disasters. The maps are cascaded to local government units for use in implementing disaster mitigation measures.

In 2012 the geo-hazard maps were made public, with access for downloading. “These geo-hazard maps need to be continuously updated. Terrains change due to typhoons [and] development. They may not be the same anymore,” Pang noted.

Logistical constraints

Leo Jasareno, director of the Department of Environment and Natural Resources, Mines and Geo Sciences Bureau (DENR-GMB), said the geo-hazard maps are updated every year, but there are other logistical constraints to consider.

“The DENR conducts orientations on the interpretation of these maps [apart from making them available online], but it is logistically difficult to cover the 1,634 municipalities and 80 provinces. Also, we have local elections every three years that makes continuity difficult. This is another factor that needs to be considered and prepared for,” he said.